Do ultra-heavy blankets reduce stress and anxiety?

Question

There's some buzz on news sites that seems to come from an article here:

Scientists Assert That Ultra-Heavy Blankets Actually Reduce Stress and Anxiety

which I think is connected to a Kickstarter project to sell a heavy blanket.

The claims are:

In the United States alone, roughly 10% of the population is affected by a sleep disorder, and a staggering 18% of the population lives with an anxiety disorder. More than 11 million people suffer from ADHD. And this is just the beginning of the problem.

"Fortunately, there is a solution that you can use today while scientists continue to work on the cures of tomorrow."

It’s called proprioceptive input (also known as “deep touch pressure stimulation”). It works by activating pressure points across your body. This relaxes the nervous system by increasing serotonin and melatonin levels while decreasing cortisol levels. In this respect, research into proprioceptive input shows that deep pressure stimulation produces a calming influence—one that decreases stress, improves sleep, and boosts mental health.

One of the most effective ways of getting this proprioceptive input? A weighted blanket.

• Is this research regarding "proprioceptive input" and its health benefits sound?
• Are heavy blankets offering efficacy to deliver the solution based on this research?

Answer 1

Honestly, more research is needed. Some research has already been done in the past 10 years, but not enough to really make solid conclusions. For example, there's no research to support the "10% of body weight + 1 pound" rule that you'll find all over the internet (example).

With kids, there's also some concern about the safety of weighted devices. The Live Science article Weighted Blankets: Harmless for Adults, Potentially Dangerous for Kids mentions two deaths that were linked to weighted blankets. (Oxford Health NHS has some guidance for use here.)

The Live Science article does a good job at citing (and linking to) studies that have been done. The first one "showed only that weighted blankets were safe for people to use, not whether they are effective in improving people's health":

In the earliest of those studies, published in 2008 in the journal Occupational Therapy in Mental Health, researchers asked 33 adults to rest under 30-lb. (13.6 kg) blankets for 5 minutes. They found that 33 percent showed a greater drop in skin conductance — a measure of arousal that is based on miniscule differences in the amount of sweat on the skin — with a weighted blanket than without. Nineteen participants said they felt more relaxed with the blanket, while eight said they felt equally relaxed either way, and three said they felt more anxious under the blanket.

The researchers noted that the results suggested that just laying down was enough to physiologically relax most participants enough that any additional benefit of the weighted blanket disappeared.

The second study was done with mental patients:

In another study, published in 2012 in the journal Australasian Psychiatry, researchers found that the use of weighted blankets in an inpatient mental psychiatric unit decreased the amount of distress the patients reported feeling, and how anxious they felt toward their health care providers. But the blankets didn't seem to improve objective measurements like aggression or the hospital's need to seclude the patients away from others, the study said.

Only one of the studies dealt with sleep:

In a third study, published in 2014 in the journal Pediatrics, researchers tested using weighted blankets to help kids with autism who had problems sleeping. The study included a "placebo" blanket, containing light plastic beads to mimic the texture of the weighted blankets, which were filled with steel beads. The researchers measured how long it took the kids in the study to fall asleep, how often they woke during the night and how long they slept in total, using both reports by parents and activity monitors that the children wore.

"We found nothing," said Dr. Paul Gringras, the head of the Children's Sleep Medicine Unit at the Evelina London Children's Hospital, who led the study. "We found no difference. It was kind of disappointing."

The last study is the most promising in terms of support for weighted blankets:

In the fourth study, published in 2016 in the Journal of the Formosan Medical Association, researchers suggested that the blankets may help people in stressful circumstances. The researchers found that the study participants who wore a weighted blanket during wisdom tooth extraction showed enhanced activity in the branch of the nervous system that takes over in times of low stress.

The results suggest that "deep-pressure input may be an appropriate therapeutic modality" for people in stressful conditions, the researchers concluded.

Answer 2

This heavy blanket may be another version of the so called 'Hug machine'. The hug machine consists of two padded boards, arranged in a V-shape. The user lies or squats between the boards, adjusts the pressure and waits for the stress to subside.

It was invented by Temple Gradin, a scientist suffering from autism. A (small) studie has found that the machine releases stress in children with autism [Edelson 1999]. Other similar devices have also been studied [Reynolds 2015, Blairs 2007]. Prof. Gradin got the idea from seeing cows calming in so called cattle squeeze chutes, it apparently works on some animals too.

I dont know why they call it 'proprioceptive input'. Proprioception is the perception of the position of your own body. That is, without looking most of us know if we are raising our hands to the ceiling, or if we are tilting our body.

Behavioral and physiological effects of deep pressure on children with autism: a pilot study evaluating the efficacy of Grandin's Hug Machine; Edelson SM1, Edelson MG, Kerr DC, Grandin T.; Am J Occup Ther. 1999 Mar-Apr;53(2):145-52

Effects of Deep Pressure Stimulation on Physiological Arousal; Stacey Reynolds; Shelly J. Lane; Brian Mullen; American Journal of Occupational Therapy, Brief Report April 2015

The clinical application of deep touch pressure with a man with autism presenting with severe anxiety and challenging behaviour; Sharon Blairs, Susan Slater, Dougal Julian Hare; British Journal of Learning Disabilities Volume 35, Issue 4, December 2007, Pages 214–220

Answer 3

The news article is pretty clearly written as an advertisement. It includes things like a small print notice of "A subsidiary of Futurism launched this product and Futurism collects a share of the sales from the items featured on this page." The link to the "buy these blankets" page shows up twice, and the wording is pretty much pure salesmanship.

They pretend to be heavily science-based, but they only link to one article in support of the idea that their product does anything worthwhile at all. That article, in turn, was written by someone (a self-proclaimed PhD) who was trying to sell his own invention for taking advantage of this effect. That paper was at least a bit mroe scientific. If we assume that its references were not simply fabricated, there's a reasonable degree of evidence that this sort of thing can be useful for the autistic, particularly autistic children.

The paper also describes an experiment, run with a total of 54 people, split into three groups of 18 each, with no control group.

Final conclusion: based on available evidence, the big thing that's happening here is that Futurism is trying to sell you something. It may or may not be a good way of giving you the effect they're pretending to offer (plausible, but unproven). That effect seems most likely to be useful to autistic children (though it's not guaranteed to be helpful even then). It's possible that nonautistic nonchildren might get some relaxation out of it, but you can say that about a great many things. Futurism doesn't really care if it works, though - they just want you to buy their weighted blankets.